A closed water lubrication system for stern shaft of ship suitable for inland river silt water area

Abstract

The technical scheme of the present application provides a ship stern shaft closed water lubrication system suitable for inland river silt water area, which comprises a bearing seat, a water lubrication stern bearing, a stern shaft, a leather cup sealing ring, a silt filter screen and a water flushing device; the water lubrication stern bearing is inserted into the bearing seat; the stern shaft is inserted into the water lubrication stern bearing; the leather cup sealing ring is arranged in three layers in the gap with the bearing seat along the axial direction of the stern shaft, the directions of the outer two layers of the leather cup sealing ring are outward, a silt treatment cabin is formed between the two layers, and the direction of the third layer of the leather cup sealing ring is inward. The present application divides the stern shaft closed water lubrication area into a silt treatment cabin and a water lubrication cabin through the arrangement of the three layers of leather cup sealing ring, the directions of the outer two layers of the leather cup sealing ring are outward, under the action of the external water pressure, the outer two layers of the leather cup sealing ring are automatically attached to the stern shaft for sealing; the water flushing device prevents silt accumulation and controllably injects water flow into the water lubrication cabin to improve the lubrication state.

Description

Technical Field

[0001] This invention relates to the field of ship propulsion system design technology, and more particularly to a closed-loop water lubrication system for ship stern shafts suitable for inland waterways with sediment. Background Technology

[0002] The stern shaft is a crucial component of a ship's propulsion system, and its operational condition directly determines the ship's reliability. However, severe wear and deterioration of the stern shaft and stern bearing are the primary causes of stern shaft failure. Traditional ship stern shafts primarily rely on oil lubrication, but due to the aging and disrepair of sealing devices, oil leaks are frequent. Therefore, water-lubricated stern shaft systems have gradually been adopted. Stern shaft water lubrication systems are mainly divided into open and closed types. Open lubrication systems directly immerse the stern shaft and stern bearing in water, offering ample lubrication, minimal pollution, and low construction costs. Consequently, open water lubrication systems for stern shafts are widely used in ships and vessels. However, the relatively soft surface of water-lubricated stern bearings cannot withstand the erosion of sediment. When sediment enters the friction pairs of the stern bearing, it is crushed or embedded in the bearing surface due to the pressure of the stern shaft, severely damaging the stern bearing and threatening the reliability of the ship's propulsion system. Therefore, open-type water-lubricated stern bearings are not suitable for use in waters with high sediment content, especially in my country's inland waterways where sediment content is generally high. Closed-type water-lubricated stern bearings are therefore more suitable for use on vessels in my country's inland waterways.

[0003] Currently, the sealing equipment for closed-loop water-lubricated stern bearing systems mainly consists of cup seals for large ships and mechanical seals for small ships. Cup seals, due to their multi-layered sealed compartment layout and pressure differential control, can achieve good sealing effects. However, during operation, the pressure within the compartments needs constant adjustment, requiring a high degree of automation or dedicated personnel, as well as extremely precise sensors. This type of sealing equipment is not only costly but also fails to address the issue of sediment buildup. Therefore, cup seals are primarily used on large ships and are not suitable for small inland waterway vessels. Currently, small ships use simple sealing rings and filler materials for internal and external isolation. These traditional sealing rings wear easily at high speeds, have short lifespans, offer limited protection, and severely neglect the problem of sediment deposition on their surface exacerbating wear. This outdated stern shaft water lubrication system not only fails to completely prevent sediment from entering the lubrication chamber but also threatens the lubrication condition of the stern shaft. Therefore, it is very important to provide a closed-loop water lubrication system suitable for inland waterway vessels in my country that can completely seal off and prevent sediment from entering the stern shaft friction pair in waters with high sediment content, while also regulating the lubrication status of the stern shaft. Summary of the Invention

[0004] In view of this, it is necessary to provide a closed-loop water lubrication system for ship stern shafts suitable for inland waterways with sediment, so as to solve the technical problem that existing stern shaft water lubrication systems not only cannot completely prevent sediment from entering the lubrication tank, but also threaten the lubrication condition of the stern shaft.

[0005] To achieve the above-mentioned technical objectives, the present invention provides a closed-loop water lubrication system for ship stern shafts suitable for inland river silt-laden waterways, comprising:

[0006] Bearing housing;

[0007] A water-lubricated stern bearing, wherein the water-lubricated stern bearing is inserted into the bearing housing;

[0008] Stern shaft, which is inserted into the water-lubricated stern bearing;

[0009] The stern cup seal ring is configured in three layers along the axial direction of the stern shaft within the gap with the bearing seat. The outermost two layers of the stern cup seal ring face outwards and form a mud and sand treatment chamber between them. The third layer of the stern cup seal ring faces inwards and forms a water lubrication chamber with the middle stern cup seal ring.

[0010] A sediment filter screen is provided both outside and inside the sediment treatment chamber for double-layer filtration of sediment.

[0011] A flushing device is used to flush mud and sand in the mud and sand treatment chamber and to inject water flow into the water lubrication chamber to control the thickness of the lubricating water film.

[0012] Furthermore, the water lubrication chamber is equipped with a water-lubricated stern bearing for the stern shaft.

[0013] Furthermore, the flushing device includes a smart water tank and a water spray gun. The water spray gun is connected to the smart water tank via a water pipe, and the water spray gun is respectively installed in the sediment treatment chamber and the water lubrication chamber.

[0014] Furthermore, it also includes an ultrasonic water film thickness measuring instrument, which is installed inside the water lubrication chamber and is used to detect the water film thickness.

[0015] Furthermore, the ultrasonic water film thickness measuring instrument is attached to the bottom outer side of the water-lubricated stern bearing.

[0016] Furthermore, it also includes a bilge water tank located below the silt treatment tank and the water lubrication tank, for receiving bilge water generated by the system.

[0017] Furthermore, the cup seal includes an outer seal and an inner seal. The inner seal extends from the inner ring of the outer seal to one side and forms a step between the inner seal and the outer ring of the outer seal. The bearing housing has a raised edge on its inner side for fitting and installing the outer seal.

[0018] Furthermore, the ultrasonic water film thickness measuring instrument calculates the thickness of the lubricating water film based on the time difference generated by the propagation of ultrasonic waves between the water-lubricated stern bearing and the stern shaft. The ultrasonic water film thickness measuring instrument converts the obtained parameters into electrical signals and transmits them to the intelligent water tank via wires.

[0019] Furthermore, the intelligent water tank responds to the electrical signal of the ultrasonic water film thickness measuring instrument. When the water film thickness is lower than a certain value, the intelligent water tank sprays a high-speed water stream into the water lubrication chamber of the water-lubricated stern bearing through the water pipe and the water spray gun.

[0020] Furthermore, the inner ring of the silt filter screen is provided with sealing rubber for fitting to the stern shaft.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. The three-layer leather cup sealing rings divide the closed water lubrication area of ​​the stern shaft into a mud and sand treatment chamber and a water lubrication chamber. The outermost two layers of leather cup sealing rings face outwards and automatically adhere to the stern shaft for sealing under the pressure of external water.

[0023] 2. A layer of sediment filter screen is installed both outside and inside the sediment treatment chamber to perform secondary filtration on the sediment that is missed by the first layer of leather cup sealing ring, preventing sediment from entering the water lubrication chamber and improving the sediment barrier effect.

[0024] 3. Use a flushing device to rinse the second layer of mud and sand filter screen to prevent mud and sand accumulation, and controllably inject water into the water lubrication chamber to increase the flow rate and volume of water when the lubricating water film becomes thin, thereby improving the lubrication condition. Attached Figure Description

[0025] Figure 1 This is a longitudinal sectional view of the overall structure of the closed-loop water lubrication system for the stern shaft in an embodiment of the present invention.

[0026] Figure 2 This is a front view of the leather cup sealing ring in an embodiment of the present invention;

[0027] Figure 3 This is a front view of the sediment filter screen in an embodiment of the present invention;

[0028] Figure 4 This is a front view of the water-lubricated stern bearing in an embodiment of the present invention;

[0029] In the diagram: 1-Stern shaft, 2-Sediment filter screen, 3-Leather cup seal ring, 4-Water spray gun, 5-Intelligent water tank, 6-Bottom water tank, 7-Water-lubricated stern bearing, 8-Ultrasonic water film thickness measuring instrument, 9-Sealing rubber, 10-Screw, 11-Propeller, 31-Outer seal ring, 32-Inner seal ring. Detailed Implementation

[0030] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0031] like Figure 1-4 As shown, the present invention provides a closed-loop water lubrication system for ship stern shafts suitable for inland river silt-prone waters, comprising a bearing housing, a water-lubricated stern bearing 7, a stern shaft 1, a lip seal ring 3, a silt filter screen 2, and a flushing device. The water-lubricated stern bearing 7 is inserted into the bearing housing; the stern shaft 1 is inserted into the water-lubricated stern bearing 7. After installation, there is a gap between the stern shaft 1 and the bearing housing. A propeller 11 is provided at one end of the stern shaft 1, and the propeller 11 is located outside the bearing housing.

[0032] The stern cup seal 3 is configured in three layers along the axial direction of the stern shaft 1 within the gap with the bearing housing for sealing. The outermost two layers of stern cup seal 3 face outwards, forming a sediment treatment chamber between them. The third layer of stern cup seal 3 faces inwards, forming a water lubrication chamber with the middle stern cup seal 3. The stern cup seal 3 is made of nitrile rubber, which has strong wear resistance and corrosion resistance. With the outermost two layers of stern cup seal 3 facing outwards, the pressure of the external water will compress the stern cup seal 3 tightly against the stern shaft 1, improving the sealing effect.

[0033] In addition, a layer of sediment filter 2 is installed both outside and inside the sediment treatment chamber for double-layer sediment filtration. Specifically, the sediment filter 2 located outside the sediment treatment chamber is positioned at the port of the bearing housing, directly opposite the propeller 11. Before entering the system, river sediment is filtered by the first layer of sediment filter 2. After the river water enters the sediment cleaning chamber of the system from the first layer of the cup seal ring 3, it comes into contact with the second layer of sediment filter 2 for further filtration, thus preventing sediment from entering the water lubrication chamber. The inner ring of the sediment filter 2 is equipped with sealing rubber 9 for fitting to the stern shaft 1. Both the sediment filter 2 and the cup seal ring 3 are fixed to the bearing housing with screws 10.

[0034] Understandably, the material of the sediment filter is 316L stainless steel, covering the first and second layers of the leather cup sealing ring 3. Its mesh size is less than 10 micrometers, which can block fine sediment from contacting the leather cup sealing ring 3 and prevent sediment from entering the system through the gaps in the leather cup sealing ring 3.

[0035] In addition, the flushing device is used to flush mud and sand in the mud and sand treatment chamber, and to inject water into the water lubrication chamber to control the thickness of the lubricating water in the water lubrication stern bearing 7.

[0036] Understandably, the flushing device can be used to rinse the silt filter screen 2 in the silt treatment chamber, thereby preventing silt accumulation; the flushing device can also be used to inject water into the water lubrication chamber to replenish the thinned water lubrication film.

[0037] In this embodiment, the cup seal 3 includes an outer seal 31 and an inner seal 32. The inner seal 32 extends from the inner ring of the outer seal 31 to one side and forms a step between the inner seal 32 and the outer ring of the outer seal 31. The inner side of the bearing seat is provided with a raised edge for the outer seal 31 to be attached and installed, wherein the direction of the inner seal 32 is the direction of the outer seal 31.

[0038] Understandably, due to the formation of the stepped platform, it has an L-shaped outer arc surface. The first two layers of the cup seal ring 3 are oriented towards the external water. Under the action of water pressure, this outer arc surface will be squeezed, thereby generating a squeezing force on the inner seal ring 32 towards the stern shaft 1. Thus, the pressure of the external water makes the cup seal ring 3 press tightly against the stern shaft 1, improving the sealing effect.

[0039] It should be noted that the saddle seal ring 3 is a double-layer design. The multi-layer arrangement of the saddle seal rings 3 in large ships is abandoned, and the air pressure control system between the saddle seal rings 3 is removed. The pressure of external water is used to control the saddle seal ring 3 to press tightly against the stern shaft 1, thereby improving the sealing effect.

[0040] In one embodiment, in order to achieve the flushing effect, the flushing device includes a smart water tank 5 and a water spray gun 4. The water spray gun 4 is connected to the smart water tank 5 through a water pipe, and the water spray gun 4 is respectively installed in the sediment treatment chamber and the water lubrication chamber. There are three water spray guns 4, two installed in the sediment treatment chamber and one installed in the water lubrication chamber. The two water spray guns 4 installed in the sediment treatment chamber are symmetrically distributed vertically and are all facing the sediment filter screen 2 in the sediment treatment chamber.

[0041] Understandably, the smart water tank 5 is used to supply water to the water spray gun 4, and the water spray gun 4 and the smart water tank 5 are connected by water pipes.

[0042] Furthermore, in order to control the lubricating water film, the ship's stern shaft closed water lubrication system also includes an ultrasonic water film thickness measuring instrument 8, which is installed in the water lubrication tank and used to detect the thickness of the lubricating water film.

[0043] The ultrasonic water film thickness measuring instrument 8 is attached to the bottom outer side of the water-lubricated stern bearing 7. The ultrasonic water film thickness measuring instrument 8 calculates the thickness of the lubricating water film based on the time difference generated by the propagation of ultrasonic waves between the water-lubricated stern bearing 7 and the stern shaft 1. The ultrasonic water film thickness measuring instrument 8 converts the obtained parameters into electrical signals and transmits them to the intelligent water tank 5 through wires.

[0044] Furthermore, the intelligent water tank 5 responds to the electrical signal of the ultrasonic water film thickness measuring instrument 8. When the water film thickness is lower than a certain value, the intelligent water tank 5 sprays high-speed water into the water lubrication chamber of the water-lubricated stern bearing 7 through the water pipe and the water spray gun 4, thereby increasing the flow rate of the lubricating water and improving the lubrication condition of the stern bearing.

[0045] In one embodiment, the closed-loop water lubrication system for the stern shaft of the ship also includes a bilge water tank 6 located below the silt treatment tank and the water lubrication tank, for receiving bilge water generated by the system.

[0046] The working principle of this invention: The rubber cup sealing ring 3 and the sediment filter screen 2 are in contact with the stern shaft 1 through a rubber seal. When the stern shaft 1 rotates, it rubs against the inner rubber rings of the rubber cup sealing ring 3 and the sediment filter screen 2. Before the river sediment water comes into contact with this system, it is first filtered by the first layer of sediment filter screen 2, which filters out most of the sediment in the river water. Then it comes into contact with the first layer of rubber cup sealing ring 3. Due to the pressure of the river water, the rubber cup sealing ring 3 is squeezed, and its rubber part is more tightly attached to the stern shaft 1, improving its sealing effect. Because the sediment content of the river is high and the draft of small vessels is shallow, a single layer of seal cannot achieve a sealing effect. After the river water enters the sediment cleaning chamber of the system from the first layer of rubber cup sealing ring 3, it comes into contact with the second layer of sediment filter screen 2 and is filtered again. Since sediment accumulation will affect the filtration effect, two water spray guns 4 continuously spray water to rinse the second layer of sediment filter screen 2. The rinsing water is provided by the intelligent water tank 5. The cleaning water and leakage water are sealed by the second layer of rubber cup sealing ring 3 to prevent them from entering the water lubrication chamber.

[0047] The ultrasonic water film thickness measuring instrument 8 is fixed at the bottom of the water-lubricated stern bearing 7. When the thickness of the lubricating water film at the bottom of the water-lubricated stern bearing 7 is lower than a certain value, the ultrasonic water film thickness measuring instrument 8 will send an electrical signal to the intelligent water tank 5. The intelligent water tank 5 will control the water spray gun 4 of the water lubrication chamber to spray high-speed water into the water lubrication chamber, thereby increasing the flow rate and volume of the water and improving the lubrication condition of the water-lubricated stern bearing 7.

[0048] This concludes the explanation of the working principle. Any content not described in detail in this specification is existing technology known to those skilled in the art.

[0049] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A closed-loop water lubrication system for ship stern shafts suitable for inland river silt-laden waters, characterized in that, include: Bearing housing; A water-lubricated stern bearing, wherein the water-lubricated stern bearing is inserted into the bearing housing; Stern shaft, which is inserted into the water-lubricated stern bearing; The stern cup seal is configured in three layers along the axial direction of the stern shaft within the gap with the bearing seat. The outermost two layers of the stern cup seal face outwards and form a mud and sand treatment chamber between the outermost two layers of the stern cup seal. The third layer of the stern cup seal faces inwards and forms a water lubrication chamber between the third layer of the stern cup seal and the middle stern cup seal. A sediment filter screen is provided both outside and inside the sediment treatment chamber for double-layer filtration of sediment. A flushing device is used to flush mud and sand in the mud and sand treatment chamber and to inject water flow into the water lubrication chamber to control the thickness of the lubricating water film. The flushing device includes a smart water tank and a water spray gun, and the water spray gun is connected to the smart water tank through a water pipe. The water spray guns are respectively installed in the mud and sand treatment chamber and the water lubrication chamber; It also includes an ultrasonic water film thickness measuring instrument, which is installed in the water lubrication chamber and used to detect the water film thickness; The ultrasonic water film thickness measuring instrument calculates the thickness of the lubricating water film based on the time difference generated by the propagation of ultrasonic waves between the water-lubricated stern bearing and the stern shaft. The ultrasonic water film thickness measuring instrument converts the obtained parameters into electrical signals and transmits them to the intelligent water tank through wires. The intelligent water tank responds to the electrical signal of the ultrasonic water film thickness measuring instrument. When the water film thickness is lower than a certain value, the intelligent water tank sprays a high-speed water stream into the water lubrication chamber of the water-lubricated stern bearing through the water pipe and the water spray gun.

2. The closed-loop water lubrication system for ship stern shafts suitable for inland river silt-laden waters according to claim 1, characterized in that, The ultrasonic water film thickness measuring instrument is attached to the bottom outer side of the water-lubricated stern bearing.

3. The closed-loop water lubrication system for ship stern shafts suitable for inland silty waterways according to claim 2, characterized in that, It also includes a bilge water tank located below the sediment treatment tank and the water lubrication tank, used to receive bilge water generated by the system.

4. The closed-loop water lubrication system for ship stern shafts suitable for inland silty waterways according to claim 3, characterized in that, The cup seal ring includes an outer seal ring and an inner seal ring. The inner seal ring extends from the inner ring of the outer seal ring to one side and forms a step between the inner seal ring and the outer ring of the outer seal ring. The inner side of the bearing housing is provided with a raised edge for the outer seal ring to be fitted and installed.

5. The closed-loop water lubrication system for ship stern shafts suitable for inland silty waterways according to claim 4, characterized in that, The inner ring of the silt filter screen is provided with sealing rubber for fitting to the stern shaft.

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